1. Field of the Invention
The present invention relates to a multicoil probe for simultaneous detection of size and depth of embedded reinforcement in concrete and method of detection using the same and more particularly, to the multicoil probe having sensing coils which are mounted in the inside and outside of an exciting coil and the method for detecting size and depth of embedded reinforcement in concrete using the same.
2. Description of the Prior Art
Generally, the reinforcements adequate to the designed structural strength are embedded in the reinforced concrete construction such as building.
When the structural safety test on the reinforced concrete construction is performed, the reinforcement embedded in the reinforced concrete construction should be detected using a reinforcement detector designed to detect its depth.
A typical reinforcement detector consists of a probe and an analysis device; the former is fabricated by a coil for reaction with the reinforcement in the concrete, and the latter with a control lever may serve not only as a power source, but also as input of size of reinforcement and detection of signal from the probe.
Referring to FIGS. 3a and 3b, the conventional probe of reinforcement detector is briefly described as follows:
With one exciting coil 12 in a housing in a certain size, the probe 10b has one sensing coil 14 mounted in the inside or outside of exciting coil 12.
Therefore, a control lever on the reinforcement detector is adjusted by the sizes of reinforcements embedded in concrete.
Commonly, one is aware of the size of the reinforcements embedded in concrete by referring to some design of the reinforced concrete building; or, the size of the reinforcements may be adjusted by assumption.
As the probe 10b is tightly held to the reinforced concrete for detection, the exciting coil 12 within the probe 10b is reacted with the reinforcement embedded in the concrete, thereby forming a magnetic field in the inside and outside of exciting coil 12.
After the sensing coil 14 detects the magnetic field formed from the inside and outside of exciting coil 12 as an induced voltage, such voltage is delivered to the analysis device.
The induced voltage released from the sensing coil 14 is detected and a analyzed by the analysis device and thus, the analysis device shows the depth of the reinforcement in values on its display.
However, the conventional probe 10b has some disadvantages as follows:
The reactivity of the probe 10b varies differently depending upon the depth and size of embedded reinforcement; namely, the thicker its size is and the shallower the embedded depth is, the larger the reactability of the probe 10b becomes.
In case where a thick reinforcement is deeply embedded in the reinforced concrete construction and a thin reinforcement is shallowly embedded in the reinforced concrete, the probe will have a similar reactability.
In this context, a majority, of the conventional probe 10b may indicate a value related to the embedded depth or size of the reinforcement, when either depth or size of the reinforcement may be given.
If one is unaware of the embedded depth and size of the reinforcement, he/her has no choice but to presume them through repeated detections over a long period of time and if this is the case, the detection values will have little accuracy.
To overcome the above shortcomings, an object of the present invention is to provide a multicoil probe for simultaneous detection of size and depth of embedded reinforcement in concrete, wherein it comprise: in a multicoil probe where the plural number of sensing coils are mounted in the inside and outside of exciting coil, the multicoil probe may serve to detect the different distribution of magnetic field formed in the inside and outside of the exciting coil, as the induced voltage value, in consideration of the fact that the distribution of magnetic field formed in the inside and outside of the exciting coil varies differently depending on the size and depth of the reinforcements embedded in the concrete.
Another object of the present invention is to provide a method for simultaneous detection of size and depth of embedded reinforcement in concrete, by comparing the actually-measured induced voltage values using the multicoil probe with the plural number of sensing coils, with those in a pre-prepared table showing each depth and size of the embedded reinforcements, even though one is unaware of the size and depth of the unknown reinforcement.
To achieve the above object, a multicoil probe of the present invention is constructed in such a manner that the plural number of the sensing coil 14 are mounted in the inside and outside of exciting coil in the probe 10a so as to measured the induced voltage values.
According to the present invention, the method for simultaneous detection of size and depth of embedded reinforcement is characterized by the following subsequent steps of:
a) pre-preparing a table for the induced voltage values which may vary differently depending upon the depth and size of embedded reinforcements, and measuring the induced voltage values on the unknown reinforcements in the concrete using the sensing coil 14 positioned in the inside and outside of exciting coil 12 of the multicoil probe 10a;
b) comparing the induced voltage values of the unknown embedded reinforcement, so detected, with those in the prepared table showing each depth and size of the embedded reinforcements, and;
c) determining the size and depth of the unknown reinforcement whose induced voltage values, so detected, are in the range established in the prepared table.